Wax powder applicator and offset eliminator



Oct. 14, 1952 w. R. DREESEN 2,613,633

WAX POWDER APPLICATOR AND OFFSET ELIMINATQR Filed Oct. 12, 1950 HWMHH, 'HIWIIW- 41 HHIHIHHHH.

Patented Oct. 14, 1952 ENT (owe f.

WAX POWDER APPLICATOR AND OFFSET ELIMINATOR William RussellDreesen, Indianapolis, Ind. v v Application October 12, 1950, Serial Nb. 1s9,se4

Thisinvention relatesto a powder applicator and ink offset eliminator for use articularly in connection with printing presses.

When a printer prints paper in endless rolls or in separate sheets, it is necessary that he take steps to prevent the offset of ink onto' the back of adjacent sheets; In addition to making an impression upon adjacent sheets as aforesaid, the ink'hasa natural tendency to cause the sheets to stick together. This is commonly called blocking? Heretofore; various means have been devised to overcome and eliminate ofiset and blocking problems. Among such means are the heat setting or heat drying method,the slip sheetingmethod and the 'steamsetting or steam precipitation method. There are; however, disadvantages inherent in each method.

It is, therefore, the primary object of this invention to provide an apparatus whichwill distribute 'a wax powder in an even, smoothfash ion upon a web, so that the coating or film thus formed will eliminate offset and blocking.

It isa further object ofthis invention 'to-p'rovide means for recapturing any; powder-that might otherwise be lost and wasted as it is sprayed upon the web.-

It is a still further object of this invention to provide a member which serves not-onlya's 'one side of the feed hopper but-also as adoctor blade of adjustable characterwhich; will prevent the building up or accumulation of powder upon the feed roll. 1 a The principal feature or the present invention resides in the construction and arrangement of the various parts of the apparatus to accomplish the abovementioned objects'JYl' 3 The full natureof the invention will be understood from the accompanying drawings and the following description and claims:

In the drawings, Fig. l is a vertical section view of the invention shown in association with the frame of a printing press and with certain of the printing rolls.

Fig. 2 is an end elevation view of the invention itself.

Fig. 3 is a side elevation view thereof.

In the drawings the frame of the printing press upon which the invention is mounted is shown generally at In. The press includes the printing rollers l I of conventional style together with the tension roll l2 and the mill roll l3. The invention is securely mounted upon the press frame by the angle irons l4 and I5. Fixedly secured by the bolts 16 or any other suitable means to said angle irons is the powder feed a 3 ago ims. (01. 118-408) hopper ll. This hopper receives the powder within the chamber [8 defined on one side bythe substantially vertical plate l9"which is preferably formed of glass or some other suitable substance which has a smooth even surface; The other side of the chamber is defined by the'side wall of the hopper and the doctor blade 2|. As will be observed by reference particularly to Fig. l, the plate although substantially vertical is. nonetheless slightly inclined towar'dsjthe hopper side defined byside wall 20 and the doctor blade. Furthermore, the bottom of the plate should either abut the hereinafter mentioned feed roll at a point vertical of its axisor; at a point not more than 5 degrees 01f center from its axis and away from the doctor blade.'. Proper feeding of wax powder is difficult, and consequently it is very important that the hopper constructionbesuch as to facilitate the desired feeding. The above arrangement accomplishes this result.

Interposed between said plate and blade is the feed roll '22 which is preferably, although not necessarily of Cumberland ground shaft type. The reduced end portions 23 of the shaft have their bearings in the end walls 24 of the hopper. One of said reduced portions extends through an end wall and beyond, it having a gear 25 mounted thereon adjacent its free end. Said gear is provided with a pulley 26 which is connected by the belt 21 to, and is powered by, the electric motor 28 mounted by the bolts 29 to the hopper.

The gear meshes with smaller gear 30which drives the feed brush 31. This brush is preferably of mane hair type. It is substantially coextensive with the feed roll and is so 13051-7 tioned relative thereto that its bristlesengage the roll. By reason of the gear ratio, it is obvious that the brush will rotate at a considerably greater rate of speed than will the roll. Furthermore, the adjacent segments of the roll and brush will naturally be rotating in the same direction. By reason of the higher rat of speed of the brush, it will brush off of the roll the powder 32 which adheres to its surfaces, and will cause the powder to spray downwardly upon the web 33. The direction of travel of the powder spray will, by reason of applicant's construction, be substantially perpendicular to the plane of the web.

In order to shield the brush and to recapture any powder that follows the centrifugal forces set up by the rapid rotation of the brush, there is provided the guard 34. This guard is substantially coextensive with the brush, and

is carried by the lever arms 35 which are pivotally mounted at 36 exteriorly of each end wall. In the event, as aforesaid, that the air currents resulting from the rapid rotation of the brush cause some of the powder particles to move in their path, the guard will prevent their loss, and will guide and direct them once again through the adjacent faces of the brush and roll.

The abovementioned levers. also carry the brush as. well as the. guard, thereduced end por-' tions 31 thereof being journalled therein. In order to permit a change of the relative relation between the faces of the brush and roll, there is provided opposed, threaded bolts 38 above and below each lever adjacent its pivotal connection.

These bolts extend through internally threadedlugs 39 secured to each end wall, and as well through lock nuts 40.

edges of the lever. When the brush is to be moved slightly away from the roll, it is necessary only to adjust each bolt upwardly. The reverse procedure is followed when the brush is to be brought into closer relation to the roll. The free ends'of the bolts are always in engagement with the side edges of each lever, therebyfirmly andsecurely retaining the levers and the brush andguard carried thereby in the desired position.

Regardless of the typeof powderused in connection with the invention, and irrespective of the type of roll employed, there will always be some powder adhering to the roll even after it has passed the brush. As a result, in order to. prevent a building up or accumulation of powder upon the roll, there is provided the doctor blade 2|. This blade is preferably formed of; spring metal or the likewhich is secured at H'to'the longitudinally disposed bar 52. While the, natural resiliency of the blade will normally urge it upwardly into engagement with. the roll, it ,is nonetheless desirable to provide the set screws 43 mounted at spaced intervals in the bar. These screws are adjustable upwardly inorder to biasthe blade into closer relation with-the blade.

While there is latitude of choiceas to the powder used with the invention, it has been found by experiencethat a wax powder of petroleum mycrocrystalline type ground to from 1 .to IO microns in diarnetenis preferable. This type of powder has sufficient dryness and hardness to enable it-to flow freely through applicant's inventionwithout caking -or-blocking. Furthermore, it has a softening point low enough to enable it to combine properly with the paraffin compound used in the bathsto whichthe printed paper is subjected after the printing and powdering operations. As a result of the use of the abovementioned powder, the paper-presents a smooth, glazed and even surface.- Furthermore,

The free ends 'of each" opposed pair of bolts are adapted to abut the side by reason of applicants invention, any offset or blocking normally occurring after the printing operation is eliminated.

While the invention has been illustrated and described in great detail in the drawings and. foregoing description, the same is to be considered as illustrative and not restrictive in char: acter.

v The invention claimedis; a

1'. An apparatus for'useiwith a printing press in applying an offset preventing medium to the freshly printed surface of a sheet or web, cornprisinga hopper for said medium having an open bottom, a rotating member rotatably connected at opposite ends to the end walls of said hopper and spanning the open bottom of said hopper, means for rotating said member, a rotating brush lying parallel to and substantially coextensive with said member and having means for rotation thereof at a faster rate of speed than said member, said brush normallybeing operably associated with said rotating.memberatapoint exteriorly of the hopper enclosed surface of said member, and adjustable means .for varying-the proximity of said. brush to said inembergsaid means. comprising a pair of substantially, Le. shaped. levers each being pivotallyconnectediat one end toan end wall of said hopperexteriorly thereof, the oppositerendfof each of said levers having. the opposite ends of said .bruslihjqur nalled therein, apair. of opposed lugs connected to each of said end Walls Xteriorly thereof, said lugs having an internally threadedv aperture formed therethrough, and. an externally threaded element adjustably disposed in each aperturela portion of said leversbeing. interposed between the free ends of-theelementsofeaoh pair.

2.;An apparatus defined-in claim l wherein the bottom portions-of said hopper arcin: wardly-converged, one of .said bottom portions being movable :toandfro into and. out of,en-. g agement with said member, and -.adjustable means'associated with said bottom portion fo'rto and fromfmovement thereof.

' WILLIAM RUSSELLDlf 'lilESliIlq,

. i F R NCES C TED.

Th f ll in refere ces a q 'rd n the filepf this patent:

UNlTED STATES PATENTS 

